$\log_{5}625 = {?}$
If $\log_{b}x=y$ , then $b^y=x$ First, try to write $625$ , the number we are taking the logarithm of, as a power of $5$ , the base of the logarithm. $625$ can be expressed as $5\times5\times5\times5$ $625$ can be expressed as $5^4$ $5^4=625$, so $\log_{5}625=4$.